A chip bin which works entirely without moving parts is previously known through U.S. Pat. No. 4,958,741. If the climate allows, such a chip bin can function satisfactorily. The principle is based on the cross-section of the chip bin being reduced in stages down towards the discharge opening in a manner which eliminates the risk of bridge formation and consequently, with certain climatic prerequisites, continuous discharge can be ensured with such a design.
The known device is based on the alternating use of oval and circular cross-sections. Such a construction leads to a disadvantage in that the oval cross-section is not optimal as far as strength is concerned. Furthermore, it is relatively complicated to manufacture and is therefore expensive.
Another chip bin which also works entirely without moving parts is previously known through SE 505 498. The known device is entirely based on the use of circular cross-sections. Although tests have shown that such a bin would function in a satisfying manner under most conditions, we did discover that under some special conditions there is a risk of bridge formation.
Now we have surprisingly revealed that all of the above problems can be eliminated by the use of reuleaux-shaped cross-sections.
The aim of the present invention is to produce a chip bin which is based on a principle of functioning preferably totally without moving parts but at the same time eliminates the above mentioned disadvantages of the known embodiments.
The solution is based on a chip bin comprising an upper container part (5), a discharge opening (4), and, arranged between the container part (5) and the discharge opening (4), a discharge zone (2, 3), preferably without moving parts, wherein the discharge zone (2, 3) in any freely chosen horizontal cross-section has a curvilinear roller shape and the number of corners in the geometrical curvilinear figure of the cross-section is more than two, preferably three, in that the cross-section of the discharge zone decreases from the container part (5) down towards the discharge opening (4), and in at least one section of said discharge zone essentially having a downwardly continuously decreasing curvilinear roller shaped cross-section.